Synthesis of single crystal films on amorphous substrates

Abstract

Forming a single crystal film includes contacting a seed crystal with one or more amorphous metallic alloy layers to form an amorphous precursor film, and annealing the amorphous precursor film to yield the single crystal film.

What is claimed is: 
     
         1 . A method of forming a single crystal film, the method comprising:
 contacting a seed crystal with one or more amorphous metallic alloy layers to form an amorphous precursor film; and   annealing the amorphous precursor film to yield the single crystal film.   
     
     
         2 . The method of  claim 1 , wherein contacting the seed crystal with the one or more amorphous metallic alloy layers comprises disposing the seed crystal on one of the one or more amorphous metallic alloy layers. 
     
     
         3 . The method of  claim 1 , wherein contacting the seed crystal with the one or more amorphous metallic alloy layers comprises disposing one of the one or more amorphous metallic alloy layers on the seed crystal. 
     
     
         4 . The method of  claim 1 , wherein contacting the seed crystal with the one or more amorphous metallic alloy layers comprises encapsulating the seed crystal between the amorphous metallic alloy layers. 
     
     
         5 . The method of  claim 1 , wherein forming the one or more amorphous metallic alloy layers comprises co-depositing constituent elements of the metallic alloy. 
     
     
         6 . The method of  claim 5 , wherein co-depositing the constituent elements comprises sputtering the constituent elements. 
     
     
         7 . The method of  claim 1 , wherein contacting the seed crystal with the one or more amorphous metallic alloy layers comprises contacting a single seed crystal with the one or more amorphous metallic alloy layers. 
     
     
         8 . The method of  claim 1 , wherein contacting the seed crystal with the one or more amorphous metallic alloy layers comprises sputtering the seed crystal through a patterned mask with a nanometer-sized opening. 
     
     
         9 . The method of  claim 1 , wherein at least one of the one or more amorphous metallic alloy layers comprises TiAl. 
     
     
         10 . The method of  claim 9 , wherein the crystallization of amorphous TiAl leads to the formation of γ-TiAl. 
     
     
         11 . The method of  claim 9 , wherein the seed crystal comprises one or more of Ti, Al, TiAl and Ag. 
     
     
         12 . The method of  claim 1 , wherein at least one of the one or more amorphous metallic alloy layers comprises NiTi. 
     
     
         13 . The method of  claim 12 , wherein the crystallization of amorphous NiTi leads to the formation of austenitic NiTi. 
     
     
         14 . The method of  claim 12 , wherein the seed crystal comprises one or more of NiTi, Cu, Cr, Fe, W, Nb and V. 
     
     
         15 . The method of  claim 1 , wherein the seed crystal has a misfit strain (ε m ) with the amorphous metallic alloy layer of less than 10%. 
     
     
         16 . The method of  claim 1 , further comprising forming at least one of the one or more amorphous metallic alloy layer at room temperature. 
     
     
         17 . The method of  claim 1 , wherein the seed crystal lowers the crystallization temperature of the one or more amorphous metallic alloy layers. 
     
     
         18 . The method of  claim 1 , wherein annealing the amorphous precursor film comprises heating the amorphous precursor film below 0.6 T m , where T m  represents the melting temperature of at least one of the one or more amorphous metallic alloy layers.